---
order: 0
title: Lighting Overview
type: Graphics
group: Lighting
label: Graphics/Light
---

Proper use of lighting can provide realistic rendering effects. This section includes the following information:

- Types of Light Sources
  - Direct Light
    - [Directional Light](/en/docs/graphics/light/directional/)
    - [Point Light](/en/docs/graphics/light/point/)
    - [Spotlight](/en/docs/graphics/light/spot/)
  - Indirect Light
    - [Ambient Light](/en/docs/graphics/light/ambient/)
    - [Ambient Occlusion](/en/docs/graphics/light/ambientOcclusion/)
- [Baking](/en/docs/graphics/light/bake/)
- [Shadows](/en/docs/graphics/light/shadow/)

> It should be noted that the number of direct lights affects performance loss. The engine limits the number of each type of direct light to no more than 10. It is generally recommended to use ambient light + some direct lights for embellishment.

## Direct Light

Direct light usually shines from an area or in a specific direction, entering the eye (camera) directly after one reflection.

## Indirect Light

Ambient light is emitted from all around and enters the eye.

## Real-time Lighting and Baked Lighting

Real-time lighting refers to Galacean calculating lighting in real-time during runtime. Baked lighting refers to Galacean performing lighting calculations in advance and baking the results into binary files (including [diffuse spherical harmonics parameters](https://www.wikiwand.com/zh-hans/%E7%90%83%E8%B0%90%E5%87%BD%E6%95%B0) and [pre-filtered environment maps](https://learnopengl-cn.github.io/07%20PBR/03%20IBL/02%20Specular%20IBL/)), and then sampling them in real-time during runtime.
